The placenta is a temporary organ that surrounds the fetus during gestation. The placenta allows for transport of gases and nutrients, and also provides other metabolic and endocrine functions. The placenta is composed of several tissue types. The umbilical cord connects the placenta to the fetus, and transports oxygen to the fetus. The umbilical cord has two arteries and a vein. Wharton's jelly, a specialized gelatinous connective tissue material, surrounds the umbilical cord to protect it from damage during fetal movement and development. The outer “shell” of the placenta is known as the “chorion.” Much of the placental disc is composed of chorionic villi, which are extensions of the chorionic villous tree. Through these structures, fetal nutrition exchange occurs. The amniotic membrane (AM) is an avascular membranous sac that is filled with amniotic fluid. This membrane is the innermost membrane surrounding a fetus in the amniotic cavity. This tissue consists of an epithelial layer and a subadjacent avascular stromal layer.